Add support for using the latest available OpenGL version

[libs/gui.git] / source / graphics / wgl / glcontext.cpp

diff --git a/source/graphics/wgl/glcontext.cpp b/source/graphics/wgl/glcontext.cpp
index 844f7a712c990a1442a7f442c4d50e5034e5b602..b0f685b582a835e38b9639073c6da8564b855e32 100644 (file)
--- a/source/graphics/wgl/glcontext.cpp
+++ b/source/graphics/wgl/glcontext.cpp
@@ -1,8 +1,24 @@
+#include <vector>
 #include <windows.h>
 #include <GL/gl.h>
+#include <GL/wglext.h>
+#include <msp/strings/lexicalcast.h>
+#include <msp/strings/utils.h>
 #include "glcontext.h"
 #include "window_private.h"
 
+using namespace std;
+
+namespace {
+
+template<typename T>
+T get_proc(const char *name)
+{
+       return reinterpret_cast<T>(reinterpret_cast<void *>(wglGetProcAddress(name)));
+}
+
+}
+
 namespace Msp {
 namespace Graphics {
 
@@ -39,7 +55,63 @@ void GLContext::platform_init(const GLOptions &opts)
        SetPixelFormat(dc, pf_index, &pfd);
 
        priv = new Private;
-       priv->context = wglCreateContext(dc);
+       if(opts.forward_compatible || opts.gl_version_major!=DEFAULT_VERSION)
+       {
+               ContextHandle fake_context = wglCreateContext(dc);
+               wglMakeCurrent(dc, fake_context);
+
+               PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribs = get_proc<PFNWGLCREATECONTEXTATTRIBSARBPROC>("wglCreateContextAttribsARB");
+               if(!wglCreateContextAttribs)
+                       throw unsupported_gl_mode(opts);
+
+               unsigned gl_version_major = opts.gl_version_major;
+               unsigned gl_version_minor = opts.gl_version_minor;
+               if(opts.gl_version_major==GLOptions::LATEST_VERSION)
+               {
+                       const char *gl_ver_ptr = reinterpret_cast<const char *>(glGetString(GL_VERSION));
+                       if(!gl_ver_ptr)
+                               throw unsupported_gl_mode(opts);
+
+                       string gl_ver = gl_ver_ptr;
+                       vector<string> parts = split(gl_ver.substr(0, gl_ver.find(' ')), '.');
+
+                       gl_version_major = lexical_cast<unsigned>(parts[0]);
+                       gl_version_minor = lexical_cast<unsigned>(parts[1]);
+               }
+
+               vector<int> ctx_attribs;
+
+               if(opts.forward_compatible)
+               {
+                       ctx_attribs.push_back(WGL_CONTEXT_FLAGS_ARB);
+                       ctx_attribs.push_back(WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB);
+               }
+
+               if(opts.core_profile)
+               {
+                       ctx_attribs.push_back(WGL_CONTEXT_PROFILE_MASK_ARB);
+                       ctx_attribs.push_back(WGL_CONTEXT_CORE_PROFILE_BIT_ARB);
+               }
+
+               if(opts.gl_version_major)
+               {
+                       ctx_attribs.push_back(WGL_CONTEXT_MAJOR_VERSION_ARB);
+                       ctx_attribs.push_back(gl_version_major);
+                       ctx_attribs.push_back(WGL_CONTEXT_MINOR_VERSION_ARB);
+                       ctx_attribs.push_back(gl_version_minor);
+               }
+
+               ctx_attribs.push_back(0);
+
+               priv->context = wglCreateContextAttribs(dc, 0, &ctx_attribs[0]);
+               if(!priv->context)
+                       throw unsupported_gl_mode(opts);
+
+               wglMakeCurrent(0, 0);
+               wglDeleteContext(fake_context);
+       }
+       else
+               priv->context = wglCreateContext(dc);
        wglMakeCurrent(dc, priv->context);
 
        ReleaseDC(window.get_private().window, dc);
@@ -53,6 +125,14 @@ GLContext::~GLContext()
        delete priv;
 }
 
+void GLContext::set_swap_interval(unsigned i)
+{
+       PFNWGLSWAPINTERVALEXTPROC wglSwapInterval = get_proc<PFNWGLSWAPINTERVALEXTPROC>("wglSwapIntervalEXT");
+       if(!wglSwapInterval)
+               throw runtime_error("wglSwapIntervalEXT not found");
+       wglSwapInterval(i);
+}
+
 void GLContext::swap_buffers()
 {
        HDC dc = GetDC(window.get_private().window);